This invention relates to an improved process for preparing agglomerated fibrous ion exchange cellulose composites. More particularly, this invention relates to a more efficient process for preparing such composites having greater ion exchange capacity than those prepared by prior art methods.
In food processing and other commercial applications the use of microbial or fungal enzymes adsorbed onto or bonded to inert carriers to provide immobilized biological catalysts has largely superseded older methods wherein soluble enzymes or whole cells of microorganisms were utilized. In general, the use of immobilized enzymes provides a number of significant advantages over the older methods. The major advantage is that the immobilized enzymes are adaptable for use in continuous conversion processes. Thus, a more efficient use of the enzyme is attained and the contact time between the enzyme and the substrate is reduced, thereby resulting in an improved product quality and a reduction in enzyme and production costs.
Although the following description and Examples are primarily directed to the utilization of agglomerated fibrous ion exchange cellulose to adsorb and immobilize glucose isomerase, it is contemplated that the agglomerated material will have the capability of adsorbing other enzymes, charged macro-molecules such as other proteins, nucleic acids and the like, and, further, would be capable of recovery of said molecules from a variety of substances such as food waste streams, e.g. recovery of protein from milk whey, meat processing streams and vegetable processing streams, reduction of BOD from waste streams, etc.
Because of the economics involved in producing glucose isomerase, it is of the utmost importance to use the isomerase under conditions whereby maximum yields of fructose are produced using minimum quantities of the enzyme. Moreover, the conditions for isomerization should be such that minimal quantities of objectionable by-products are produced.
In recent years, more economical methods for producing fructose-containing solutions have been developed utilizing glucose isomerase bound or immobilized on inert support materials. Such materials include various polymeric substances such as derivatized cellulose, ion exchange resins and synthetic fibers, glass, insoluble organic and inorganic compounds, etc. Glucose isomerase has also been encapsulated or englobed in suitable materials but such preparations suffer from the disadvantage that they generally cannot be reused.